Photographic materials having reduced static chargeability and method for their production

ABSTRACT

The inclusion of both a substantially fluorinated surfactant and a non-fluorinated betaine and/or N-oxide surfactant into photographic layers and materials reduces the static chargeability of such materials.

United States Patent Cavallo et al.

[4 1 May 20, 1975 PHOTOGRAPHIC MATERIALS HAVING REDUCED STATIC CHARGEABILITY AND METHOD FOR THEIR PRODUCTION Inventors: Elio Cavallo, Carcare; Fulvio Furlan, Savona, both of Italy Assignee: Minnesota Mining and Manufacturing Company, St. Paul, Minn.

Filed: July 18, 1973 Appl. No.: 380,410

Foreign Application Priority Data [56] References Cited UNITED STATES PATENTS 2,420,6l] 5/1947 Mueller 96/87 A 3,775,126 ll/l973 Babbitt et al. 96/1 l4.2 X

Primary Examiner-Norman G. Torchin Assistant ExaminerAlfonso T. Suro Pico Attorney, Agent, or FirmAlexander, Sell, Steldt & DeLaHunt [57] ABSTRACT The inclusion of both a substantially fluorinated surfactant and a non-fluorinated betaine and/or N-oxide surfactant into photographic layers and materials reduces the static chargeability of such materials.

28 Claims, No Drawings PHOTOGRAPHIC MATERIALS HAVING REDUCED STATIC CHARGEABILITY AND METHOD FOR THEIR PRODUCTION The present invention relates to a method for reducing the chargeability of photographic layers and photographic elements, to photographic layers and photographic elements obtained with such a method.

A photographic material generally consists of a base, at least one layer of a silver halide emulsion dispersed in a hydrophilic colloidal binder and, possibly, of at least one protective layer for such an emulsion, essentially consisting of a hydrophilic colloidal binder. Such a protective layer can be found either outside or inside such a photographic material (in this last case, for instance in color photographic materials, it is called interlayer). It is also known that a photographic material may include sub-layers, anti-halo layers and other auxiliary layers adjacent or not the emulsion layers. A photographic material suitable for radiography particularly consists of a base, at least two emulsion layers each coated on one surface of said base and at least two protective layers for said emulsion layers. Such amaterial may also contain two sub-layers coated between the emulsion layers and the base.

It is further known that it is desirable to produce photographic layers, i.e., emulsion layers and auxiliary layers (such as for instance protective layers, interlayers, sublayers and anti-halo layers) exhibiting a reduced static chargeability. During preparation, packaging or use, such layers are prone to stresses which may cause electrostatic charges to be formed, which by discharging produce undesired sensitizations in light-sensitive emulsions. Particularly, a radiographic material should be usable in angiographic tables (AOT) and in rapid machines wherein the film is conveyed at a high speed by means of rollers which exert thereon a strong pressure and friction action.

In such use, strong electrostatic charges are formed at the surface of contact between the protective layer and the rollers, thus giving rise to undesired sensitizations. Such sensitizations are equivalent to undesired exposures and after the processing sequence the photographic element will have variedly shaped specks which can be found above all along the film sides where the contact rollers/protective layers occurs.

In addition to a reduced chargeability, radiographic materials suitable for AOT must exhibit a rather high slipperiness index which reduces the dangers of the apparatus jamming. In some cases, indeed, the slipperiness index can be related to the static chargeability itself.

The chargeability of the layers is generally due to the fact that the layers essentially consist of gelatin or of another hydrophilic colloidal binder equivalent to gelatin which exhibits a low work function, i.e., a positive type chargeability. Such a chargeability is generally modified by the presence of surfactants which induce a positive or a negative type chargeability into the layers according to their nature. Non-fluorinated anionic surfactants of the type known to those skilled in the art generally induce a positive type chargeability into the layers. Fluorinated anionic, non-ionic N-oxide or betaine surfactants induce a negative type chargeability into the same layers. Betaine and/or N-oxide non-fluorinated surfactants in combination with nonfluorinated anionic surfactants do not substantially improve the static characteristics of the photographic layers, while on the contrary they improve slipperiness characteristics. Fluorinated surfactants in combination with anionic non-fluorinated surfactants improve the static characteristics of the photographic layers only at a certain range of relative humidity and leave slipperiness characteristics unaltered.

The main scope of the present invention is that of providing a method for removing or at least reducing the electrostatic chargeability of the photographic layers and above all of the protective layers, the photographic material consists of.

A further scope of the present invention is that of providing photographic and radiographic materials having improved characteristics of electrostatic chargeability.

Another scope of the present invention is that of providing photographic and radiophotographic materials having improved characteristics of static chargeability ahd slipperiness.

According to the present invention, we have found that the use of fluorinated surfactants in combination with non-fluorinated betaine and/or N-oxide surfactants allows the chargeability of photographic layers to be reduced at all relative humidities for all of those photographic layers having a positive chargeability including chargeability due to the presence of nonfluorinated anionic surfactants.

Non-fluorinated anionic surfactants, normally used in photography, for instance as coating, coagulant or dispersing agents, are surfactants of the type including hydrophobe group linked to an anionic hydrophilic group directly or by means of a bridge consisting of a divalent organic residue, as expressed by the following formula:

wherein R is a non-fluorinated aliphatic, aromatic or a mixed hydrocarbon residue substituted or not substituted and preferably a linear or ramified alkyl group having from four to 18 carbon atoms or an aryl group substituted with one or more alkyl groups altogether having from four to 18 carbon atoms;

A is a chemical bond or a divalent organic residue, preferably a carbonyl, a sulphonyl, an amino or an alkylene group preferably having from one to three carbon atoms, an oxygen atom or groups consisting of two or more of the above-mentioned groups, such as for instance carbonylamino, sulphonylamino, aminocarbonyl, aminosulphonyl, ester or polyoxyalkylene groups preferably containing from two to forty oxyalkylene unities; and

X is an anionic group of the sulphonate, carboxylate,

phosphate and sulphate type.

Anionic surfactants of this type are described for instance in Schwarz et al. Surface Active Agents and Detergents, Vol. I and II, Interscience Publ., in the US. Pat. Nos. 2,992,108; 3,068,101; 3,201,152; 3,165,409; in the French Pat. Nos. 1,556,240; and 1,497,930 and in the British Pat. Specification Nos. 580,504 and 985,483. They will be hereinafter called non-fluorinated anionic surfactants.

With fluorinated surfactants according to the present invention we mean herewith any type of fluorinated surfactants capable of inducing a negative charge into the photographic layers containing them. They include preferably a hydrophobic portion R linked to a hydrophilic portion Y of every kind, may it be anionic, nonionic, cationic betaine or N-oxide, by means of a bridge A which represents a chemical bond or a divalent organic residue, as expressed by the formula:

wherein:

R F is a substantially fluorinated hydrocarbon residue, preferably a fluorinated alkyl group having at least two carbon atoms and more preferably from two to 18 carbon atoms;

A is a chemical bond or a divalent organic residue,

preferably of the above-defined type; and

Y is a hydrophilic group of any type, may it be non ionic, anionic, cationic, betaine or N-oxide, and preferably a cationic group.

A substantially fluorinated hydrocarbon residue is by definition a fluorinated saturated monovalent nonaromatic radical of at least two carbon atoms. The aliphatic chain may be straight, branched, or, if sufficiently large, cyclic and may include oxygen or trivalent nitrogen atoms bonded only to carbon atoms. A fully fluorinated radical is preferred, but hydrogen or chlorine atoms may be present as substituents provided that not more than one atom of either is present for every two carbon atoms, and preferably, the radical contains at least a terminal perfluoromethyl group. While radicals containing a larger number of carbon atoms will function adequately, compounds containing not more than about 20 carbon atoms are preferred since larger radicals usually represent a less efficient utilization of fluorine than is possible with shorter chains. Fluoroaliphatic radicals containing about two to eight carbon atoms are most preferred.

Groups of this type are for instance a polyoxyalkylene group including from two to 40 oxyalkylene unities, wherein the alkylene group preferably has from one to three carbon atoms, a group of the sulphonate, carboxylate, sulphate or phosphate type, or an ammonium or phosphonium group, or a betaine group including a cation of the ammonium type and an anion of the carboxylate or sulphonate type, or a N-oxide group. Groups of this type are, for instance:

R R and R are hydrogen or alkyl group having from one to 10, preferably from one to six carbon atoms, wherein said alkyl group possibly can be substituted for instance with an aryl group, preferably phenyl;

R and R or R R and R altogether also represent the non-metallic atoms necessary to form a heterocyclic quatemized nitrogen nucleus, such as for instance piridinium and imidazolinium',

D represents an anion such as for instance halide,

sulphate;

B is an alkylene group possibly comprising a heterous bond, preferably having from one to six carbon atoms; and

X is a carboxylate or sulphonate anion.

Fluorinated surfactants useful to the scope of the present invention are for instance described in U.S. Pat. Nos. 2,759,019; 2,764,602; 3,589,906; in the Belgian Pat. No. 739,245; and in the French Pat. No. 2,025,688.

With betaine or N-oxide non-fluorinated surfactants, all those surfactants which present betaine or N-oxide hydrophilic groups are hereby intended. This group is preferably linked to a hydrophobic group R by means of a bridge A, as expressed in the following formula:

wherein:

R and A preferably represent groups of the abovedefined type; and

Z preferably represents a betaine group, such as for instance of the type comprising a cation of the ammonium type and an anion of the carboxylate and sulphonate type, such as for instance of the abovedescribed type or a group of the N-oxide type, as described above.

Betaine compounds of this type are for instance described in the U.S. Pat. No. 3,573,049 and N-oxide compounds of this type are for instance described in McCutcheons Detergents and Emulsifiers 1963 Annual (page 8).

Briefly, the present invention concerns a method for reducing or removing the electrostatic chargeability of a photographic layer which consists of introducing at least a fluorinated surfactant, as defined above and at least a non-fluorinated betaine and/or N-oxide surfactant, as defined above, said layer preferably containing at least a non-fluorinated anionic surfactant.

The present invention particularly relates to a method for reducing or removing the electrostatic chargeability of a photographic layer which consists of introducing into said layer a cationic fluorinated surfactant, preferably comprising a partially or wholly fluorinated aliphatic hydrocarbon residue linked, by means of a chemical bond or a divalent organic residue comprising a carbonylamino or sulphonylamino group, with a chemical residue comprising an ammonium group, and at least a betaine or N-oxide nonfluorinated surfactant preferably a betaine comprising a non-fluorinated aliphatic hydrocarbon residue linked, by means of a divalent organic residue comprising a carbonylamino or sulphonylamino group, with a betaine residue, said layer containing an anionic nonfluorinated surfactant.

The present invention relates to a photographic layer obtained with the above-described method and to a photographic element containing said layer.

The present invention further refers to an improved photographic material including:

a. a base;

b. at least one layer of a silver halide emulsion;

c. at least one protective layer for said emulsion layer, said emulsion layer and/or said protective layer containing at least one non-fluorinated anionic surfactant, as defined above,

the improvement lying in that said emulsion and/or said protective layer contains at least a fluorinated and a non-fluorinated betaine and/or N-oxide surfactant, as defined above.

The present invention particularly relates to a material of the above-described type containing the fluorinated and the non-fluorinated betaine and/or N-oxide surfactant at least in said protective layer for said emulsion layer.

More particularly, the present invention relates to an improved radiographic material including:

a. a base;

b. two emulsion layers each coated on one surface of said base;

c. two protective layers of said emulsion layers, said protective layers containing at least a nonfluorinated anionic surfactant, as defined above, the improvement lying in that said protective layers contain at least one fluorinated and one nonfluorinated betaine and/or N-oxide surfactant, as described above.

The present invention particularly relates to a material of the above defined type containing at least a fluorinated cationic surfactant, at least a non-fluorinated betaine or N-oxide surfactant and at least a nonfluorinated anionic surfactant, said fluorinated cationic surfactant preferably comprising a partially or wholly fluorinated aliphatic hydrocarbon residue linked, by means of a chemical bond or a divalent organic residue comprising a carbonylamino or sulphonylamino group, with a chemical residue comprising an ammonium group; and said non-fluorinated betaine surfactant preferably comprising a non-fluorinated aliphatic hydrocarbon residue linked with a betaine residue by means of a divalent organic residue comprising a carbonyl-amino or sulphonylamino group.

Compounds of the non-fluorinated anionic surfactant type, as defined above, are for instance:

6. Olen-C01? (CH -SO Na Stearyl-( 00 1i -NHCO-CH SO Na CH -CONH C l'l H-COONa l ca coo 6 I 21. C F S0 NHC H N (c11 ca;@ 01

24. C F SO N (CI-I C H N (CI-I T 25. C F CONI-IC H N (CI-I9 I 9 25 bis. c F so Nac H 11: oso oc n Compounds of the non-fluorinated betaine and N- oxide surfactant type, as defined above, are for instance:

26. *cocco CONI-I (CI-1 N (CH CI-I COO 27. stearyl N (CI-I9 CH COO 28. Lauryl N (CI-I9 (CI-1 COO 29. stearyl N (CH (CI-I S 30. 00600 CONH (CH N (CH 31. lauryl 1801 1 cocco represents a mixed blend of groups derived from the reaction of coconut oils with amines. The nature of the resultant composition is about 65% C I-1 (lauric acid), C I-I (mirystic acid), 15% C, H (palmitic acid) and 15% C H (capric acid).

The above-listed compounds can be found on the market or prepared in a conventional way.

Particularly, compound no. 17 has been prepared in the following way:

To a solution of of 127 g.

propyl alcohol was added 0.2 mole of 25% methanolic Na 0 CH The mixture was digested at 60-70C for 1.5 h., then cooled and filtered. The

precipitate was washed with water to give a fine granular powder of the formula:

To a solution of 3.8 g. of CICI-I COOI-I in g. of isopropyl alcohol and 32 g. of methanol was added 8.6 g.

of 25% Na 0 CH in methanol and then 20g. of the.

Infrared spectroscopy showed a strong carbonyl bond at 6.2a. Calculated: 30.2% C, 3.1% H, 5.0% N. Found: 28.3% C, 3.0% H, 5.0% N.

The photographic layers of the present invention comprise or essentially consist of hydrophilic colloidal binder. Such a hydrophilic colloidal binder preferably is gelatin or any other film-forming binder permeable to the conventional processing baths for photographic materials alone or mixed with gelatin.

Such a hydrophilic binder can obtain, dispersed, hydrophobe polymer particles in order to improve the physical characteristics of the layers, thus obtained. Particles of this type consist for instance of polyethylacrylate obtained for instance under the form of a latex.

Such layers can be hardened with hardeners known to those skilled in the art, such as for instance formaldehyde, glyoxale, succinaldehyde, glutaraldehyde, resorcinaldehyde, mucochloric acid, epoxides used alone or in association and can contain any other coating materials known to those skilled in the art.

In the case of photographic emulsion layers, the layers will contain, dispersed, silver halides, such as for instance bromide, iodide and chloride or mixtures thereof and antifog compounds and stabilizers in association therewith. In the case of color emulsions, such as layers can also contain couplers which upon color development with p-phenylene diamines give rise to yellow, magenta and cyan dyes.

The above is described for instance in C. E. Kenneth Mees and T. B. James, The Theory of the Photographic Process, third edition.

Photographic layers of the above-mentioned type can contain anionic non-fluorinated surfactants preferably in a quantity ranging from 0.1 to 25, preferably from 1.5 to 5 g. per g. of gelatin or of another equivalent hydrophilic colloid. The fluorinated and the nonfluorinated betaine or N-oxide surfactants are for instance added preferably in a quantity which respectively ranges from 0.1 to 25 and from 0.5 to 30 g. per 100 g. of gelatin or equivalent colloid, and more preferably in a quantity which respectively ranges from 0.1 to 5 and from 5 to 15 g. per 100 g. of gelatin.

The above-described surfactants can be both introduced into the photographic layers before being coated under the form of solutions, as known to those skilled in the art. The solvents preferably used are water, alcohol and acetone or mixtures thereof or any other solvent, provided that it causes no damage to the photgraphic emulsion.

The chargeabilitiy of the photographic layers according to the present invention and of the photographic materials they consist of has been estimated with the following method.

A ring of the material is stretched by several steel rollers and conveyed upon friction by a steel and gum roller. By means of a magnetic clutch, the ring is started to move from a speed till to reach a given speed and the discharged immediately before the steel/gum roller couple by means of a 3M Type 210 electrostatic discharger. The charge generated on the film by the passage between these two rollers is then measured. The characteristics of the device and the measurement conditions are the following:

film speed 60 m/minute;

film tension 0.55 kg/cm.;

pressure between the steel and the gum roller l kg/cm.;

diameters of the gum and the steel roller 8.2 cm.

and 2.5 cm., respectively.

The charge density has been measured at a distance of cm. from the roller axis.

In particular, the slipperiness of the radiographic material in sheets has been measured by means of an ElemaSchonander device, wherein the sheet is placed between two intensifying screens, of the type known in radiography, on which a constant pressure is exerted. The force necessary to pull out the film from the screens gives a slipperiness measure. Obviously, the higher the slipperiness, the lower is such a force.

EXAMPLE 1 A silver bromo-iodide (98% bromide and 2% iodide) radiographic emulsion has been digested and added with the normal coating finals known in the photographic field (antifog agents, stabilizers, harderners, etc.). The emulsion, thus obtained, has been coated on both surfaces of a polyester base with the aid of anionic surfactants. Two protective layers have then been coated on both emulsion layers: They consisted of gelatin and contained silica, as a matting agent, and the above-described Compound No. 8 and No. 2, as a coating surfactant, respectively in a quantity of 0.72 and 1.6 g. per 100 g. of gelatin. The same protective layers have been added or not with the surfactants of the present invention.

The electrostatic chargeability values for the materials with the additions of the various surfactants, measured as described above, are shown in Table l. The quantity in grams of such compounds must be referred to 100 g. of gelatin.

TABLE l-Continued Compound Charge pc/m ll 26 25% RH. 50% RH. RH.

0.15 g. 10g. 0.8 |.5 0 0.25 g. 10 g. 5 7 0.3 1.0 g. 10g. 10 9 0.3 4.0 g 10 g 9 10 0 13 26 25% R.H. 50% RH. 70% RH.

0 g. 0 g. 9 9 2.7 0.25 g. 0 g. 7 6 0.8 1.0 g. 0 g 4.6 l 0.5 4.0 g. 0 g. l0 4 0.7 0.25 g. 10 g. 8.4 5 0 1.0 g. 10 g. 7.2 l 0 4.0 g. 10 g. 6.4 3 0 14 29 25% RH 50% R.H. 70% RH.

12 28 25% RH. 50% RH. 70% RH EXAMPLE 2 A material like that described in example 1 was produced. Such a meterial contained or did not contain compounds nos. 16 and 26 of the present invention. The hereinafter enclosed table 2 gives the electrostatic chargeability values measured as described above. The quantities in grams of the compounds added to the emulsion must be referred to g. of gelatin.

The same material, as described above, added or not with Compounds No. 12 and No. 26, according to the present invention, has been tested from the point'of view of the antistatic characteristics in an angiographic table. The material, cut into sheets andpassed through the table, has been developed with a conventional photographic developer suitable to radiography, fixed and washed. We have then examined the sheets to see if they contained specks caused by electrostatic sensitizations. The results are shown in Table 3. The quantities of the additions are referred to 100 g. of gelatin.

The same material, as described above, added or not with Compounds No. 12 and No. 26 according to the present invention, has been tested from the point of view of its slipperiness characteristics with the abovedescribed method. The results are shown in Table 4.

The quantities must be referred to 100 g. of gelatin in the protective layer.

TABLE 4 Compound Slipperiness 0 890 g. 0.15 0 900 g. 0.25 O 870 g.

EXAMPLE 5 The same material, as described above, added or not with Compounds No. 12 and 30 according to the present invention has been tested from the point of view of its antistatic characteristics with the above-described method. The results are shown in Table 5.

The quantities must be referred to 100 g. of gelatin in the protective layer.

TABLE 5 Compound Charge [16/111 12 3O R.H. 50% R.H. 70% R.H.

0 0 l0 8 2.1 0.15 O "3.0 -2.7 2.8 0.25 0 -6.8 5.7 "5.1 0 10 9.1 6.8 0.2 0.15 10 -0.5 -l.5 0.2 0.25 10 1.8 '2.0 0.1

What we claim is:

l. A method for reducing the chargeability of photographic layers, upon a support, which essentially consist of a hydrophylic colloidal binder comprising gelatin, said method consisting of introducing at least one surfactant having a substantially fluorinated cation or anion bonded to a hydrophilic group and at least one of a nonfluorinated betaine orN-oxide surfactant into said layers by mixing the hydrophilic colloidal binder and surfactants prior to formation of the photographic layer containing the surfactants.

2. The method of claim 1, characterized in that said fluorinated surfactant is a surfactant having a substantially fluorinated cation.

3. The method for reducing the chargeability of photographic layers of claim 1, said photographic layers containing a non-fluorinated anionic surfactant, characterized in that at least one fluorinated cationic surfactant comprising a substantially fluorinated aliphatic hydrocarbon residue linked, by means of a chemical bond or a divalent organic residue comprising a carbonylamino or a sulphonylamino group, with a chemical residue comprising an ammonium group, and at least a non-fluorinated betaine surfactant comprising a non-fluorinated aliphatic hydrocarbon residue linked with a betaine residue by means of a divalent organic residue comprising a carbonylamino group, are introduced into said layers by mixing the hydrophilic colloidal binder and surfactants prior to formation of the photographic layer containing the surfactants.

4. Method for reducing the chargeability of a photographic material comprising:

a. a base;

b. at least one layer of a silver halide emulsion dispersed in a hydrophylic colloidal binder; which consists of introducing at least one surfactant having a substantially fluorinated anion or cation and at least a non-fluorinated betaine and/or N-oxide surfactant into the said at least one emulsion layer by mixing the surfactants and binder prior to formation of the layer containing the surfactants.

5. A photographic layer, on a support, essentially consisting of a hydrophilic colloidal binder comprising gelatin characterized in that it contains at least one surfactant having a substantially fluorinated cation or anion and at least a non-fluorinated betaine and/or N- oxide surfactant.

6. A photographic layer on a support, the layer essentially consisting of a hydrophylic colloidal binder comprising gelatin, characterized in that it contains at least one surfactant having a substantially fluorinated anion or cation, at least one selected from the group of nonfluorinated betaine and N-oxide surfactants, and at least one non-fluorinated anionic surfactant.

7. The photographic layer of claim 5 wherein said fluorinated surfactant is fluorinated cationic surfactant.

8. The photographic layer of claim 7, characterized in that it contains a non-fluorinated anionic surfactant; at least a fluorinated cationic surfactant comprising a partially or wholly fluorinated aliphatic hydrocarbon residue linked, by means of a chemical bond or a divalent organic residue comprising a carbonylamino or a sulphonylamino group, with a chemical residue comprising an ammonium group; and at least a non fluorinated betaine residue comprising a non-fluorinated aliphatic hydrocarbon residue linked with a betaine residue by means of a divalent organic residue comprising a carbonylamino or sulphonylamino group.

9. The photographic layer of claim 5, characterized in that the fluorinated surfactant corresponds to the formula:

wherein:

R represents a substantially fluorinated hydrocarbon residue; A is a chemical bond or a divalent organic residue;

and Y represents an anionic, non-ionic, or cationic betaine or N-oxide hydrophylic group. 10. The photographic layer of claim 9, characterized in that R is a fluorinated alkyl group having from two to eight carbon atoms, A is a chemical bond or a divalent organic residue comprising at least a carbonyl, sulphonylamino, alkylene residue having from one to three carbon atoms, oxygen, carbonylamino, 'sulphonylamino, aminocarbonyl, aminosulphonyl, ester, polyoxyalkylene having from two to 40 oxyalkylene unities and/or R is an alkyl group having from four to 18 carbon atoms and Z is a betaine hydrophylic group comprising an ammonium group and (an anionic group or a group comprising an N-oxide bond.

11. A photographic element comprising at least a base and a photographic layer according to any ofclaim 5.

12. In a photographic element including:

a. a base; i

b. two layers of silver halide emulsion, dispersed in a hydrophylic colloidal binder comprising gelatin, each emulsion layer being coated on separate faces of said base;

0. two protective layers, essentially consisting of a hydrophylic colloidal binder comprising gelatin, each protective layer coated on one of said emulsion layers, said protective layer containing at least a nonfluorinated anionic surfactant,

the improvement, which lies in that said protective layers contain at least one surfactant having a substantially fluorinated anion or cation and at least a nonfluorinated betaine and/or N-oxide surfactant.

13. The photographic element of claim 12, characterized in that said fluorinated surfactant is a fluorinated cationic surfactant.

14. The photographic element of claim 13, characterized in that it contains said fluorinated cationic surfactant comprising a partially or wholly fluorinated aliphatic hydrocarbon residue linked, by means of a chemical bond or a divalent organic residue comprising a carbonylamino or sulphonylamino group, with a chemical residue comprising an ammonium group; and at least a non-fluorinated betaine surfactant comprising a non-fluorinated aliphatic hydrocarbon residue linked with a betaine residu'e by means of a divalent organic residue comprising a carbonylamino or a sulphonylamino group.

15. The improved photographic element according to claims 12, characterized in that the fluorinated surfactant corresponds to the formula:

eight carbon atoms, A is a chemical bond or a divalent residue at least comprising a carbonyl, sulphonyl, amino, alkylene residue having from one to three carbon atoms, oxygen, carbonylamino, sulphonylamino,

aminocarbonyl, ester, polyoxyalkylene having from two to 40 oxyalkylene unities and/ or R is an alkyl group having from four to 18 carbon atoms and Z is a hydrophylic betaine group comprising an ammonium and an anionic group or a group comprising an N-oxide bond.

17. The method of claim 4 wherein the photographic material further comprises at least one protective layer comprising gelatin for said emulsion layer, and where said surfactants are present in at least one of said emulsion and'protective layers.

18. The process of claim 4 wherein the emulsion layer further contains at least one non-fluorinated anionic surfactant.

19.'The process of claim 17 wherein the at least one of said emulsion or protective layers containing the surfactants further contains at least one non-fluorinated anionic surfactant.

20. The photographic layer of claim 6 wherein said fluorinated surfactant is a fluorinated cationic surfactant.

21. The photographic layer of claim 6, characterized in that it contains a non-fluorinated anionic surfactant; at least a fluorinated cationic surfactant comprising a partially or wholly fluorinated aliphatic hydrocarbon residue linked, by means of a chemical bond or a divalent organic residue comprising a carbonylamino or a sulphonylamino group, with a chemical residue comprising an ammonium group; and at least a nonfluorinated betaine residue comprising a nonfluorinated aliphatic hydrocarbon residue linked with a betaine residue by means of a divalent organic residue comprising a carbonylamino or a sulphonylamino group.

22. The photographic layer of claim 6, characterized in that the fluorinated surfactant corresponds to the formula:

R A Y wherein:

R represents a substantially fluorinated hydrocarbon residue; A is a chemical bond or a divalent organic residue;

and Y represents an anionic, non-ionic, or cationic betaine or N-oxide hydrophylic group. 23. The photographic layer of claim 9 wherein at least one of the non-fluorinated betaine and N-oxide surfactants correspond to the formula:

wherein:

R is a non-fluorinated hydrocarbon residue, A is a chemical bond or a divalent organic residue,

and Y Z represents a betaine or N-oxide hydrophilic group. 24. The photographic layer of claim 6 wherein at least one of the non-fluorinated betaine and N-oxide surfactants correspond to the formula:

wherein:

R is a non-fluorinated hydrocarbon residue, A is a chemical bond or a divalent organic residue,

and Z represents a betaine or N-oxide hydrophilic group. 25. The photographic layer of claim 22, characterized in that R is a fluorinated alkyl group having from two to eight carbon atoms, A is a chemical bond or a divalent organic residue comprising at least a carbonyl, sulphonylamino, alkylene residue having from one to three carbon atoms, oxygen, carbonylamino, sulphonylamino, aminocarbonyl, aminosulphonyl, ester, polyoxyalkylene having from two to 40 oxyalkylene unities and/or R is an alkyl group having from four to 18 carbon atoms and Z is a betaine hydrophylic group comprising an ammonium group and/or an anionic group or a group comprising an N-oxide bond.

26. A photographic element comprising at least a base and a photographic layer according to claim 6.

27: The improved photographic element according to claim 14 characterized in that the fluorinated surfactant corresponds to the formula: wherein:

R F represents a partially or wholly fluorinated hydrocarbon residue; A represents a chemical bond or a divalent organic residue; and Y represents a hydrophylic anionic, non-ionic, meationic betaine or N-oxide group; and/or the non-fluorinated betaine and/0r N-oxide surfactant corresponds to the formula:

wherein:

R represents a non-fluorinated hydrocarbon residue;

A has the same meaning as said above;

Z represents a hydrophylic betaine or N-oxide group.

28. The photographic element of claim 27, characterized in that R is an alkyl group having from two to eight carbon atoms, A is a chemical bond or a divalent residue at least comprising a carbonyl, sulphonyl, amino, alkylene residue having from one to three carbon atoms, oxygen, carbonylamino, sulphonylamino, aminocarbonyl, ester, polyoxyalkylene having from two to 40 oxyalkylene unities and/or R is an alkyl group having from four to 18 carbon atoms and Z is a hydrophylic betaine group comprising an ammonium and an anionic group or a group comprising an Noxide bond. =1:

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION PATENT NO. 3 88 4 699 DATED May 20, 1975 INVENTORB) 1 Elio Cavallo and Fulvio Furlan i c.---'nfied 531a? :ansem: ihe above--ident1fled patent and that said Letters Patent 25s Fla-sir,-

shown him Col. 7, line 15, "CH2COO+" should be "013 000 Col. 15, line 15, after corresponds to the for'mulafi add --R A Y.

. Signed and Sealed this fourteenth D ay of October 19 75 [SEAL] A ttes t:

RUTH C. MASON C. MARSHALL DANN Arresting Officer Commissioner ofParents and Trademarks 

1. A METHOD FOR REDUCING THE CHARGEABILITY OF PHOTOGRAPHIC LAYERS, UPON A SUPPORT, WHICH ESSENTIALLY CONSIST OF A HYDROPHYLIC COLLOIDAL BINDER COMPRISING GELATINM SAID METHOD CONSISTING OF INTRODUCING AT LEAST ONE SURFACTANT HAVING A SUBSTANTIALLY FLUORINATED CATION OR ANION BONDED TO A HYDROPHILIC GROUP AND AT LEAST ONE OF A NONFLUORONATED BETAINE OR N-OXIDE SURFACTANT INTO SAID LAYERS BY MIXING THE HYDROPHILIC COLLOIDAL BINDER AND SURFACTANTS PRIOR TO FORMATION OF THE PHOTOGRPHIC LAYER CONTAINING THE SURFACTANTS.
 2. The method of claim 1, characterized in that said fluorinated surfactant is a surfactant having a substantially fluorinated cation.
 3. The method for reducing the chargeability of photographic layers of claim 1, said photographic layers containing a non-fluorinated anionic surfactant, characterized in that at least one fluorinated cationic surfactant comprising a substantially fluorinated aliphatic hydrocarbon residue linked, by means of a chemical bond or a divalent organic residue comprising a carbonylamino or a sulphonylamino group, with a chemical residue comprising an ammonium group, and at least a non-fluorinated betaine surfactant comprising a non-fluorinated aliphatic hydrocarbon residue linked with a betaine residue by means of a divalent organic residue comprising a carbonylamino group, are introduced into said layers by mixing the hydrophilic colloidal binder and surfactants prior to formation of the photographic layer containing the surfactants.
 4. Method for reducing the chargeability of a photographic material comprising: a. a base; b. at least one layer of a silver halide emulsion dispersed in a hydrophylic colloidal binder; which consists of introducing at least one surfactant having a substantially fluorinated anion or cation and at least a non-fluorinated betaine and/or N-oxide surfactant into the said at least one emulsion layer by mixing the surfactants and binder prior to formation of the layer containing the surfactants.
 5. A photographic layer, on a support, essentially consisting of a hydrophilic colloidal binder comprising gelatin characterized in that it contains at least one surfactant having a substantially fluorinated cation or anion and at least a non-fluorinated betaine and/or N-oxide surfactant.
 6. A photographic layer on a support, the layer essentially consisting of a hydrophylic colloidal binder comprising gelatin, characterized in that it contains at least one surfactant having a substantially fluorinated anion or cation, at least one selected from the group of non-fluorinated betaine and N-oxide surfactants, and at least one non-fluorinated anionic surfactant.
 7. The photographic layer of claim 5 wherein said fluorinated surfactant is fluorinated cationic surfactant.
 8. The photographic layer of claim 7, characterized in that it contains a non-fluorinated anionic surfactant; at least a fluorinated cationic surfactant comprising a partially or wholly fluorinated aliphatic hydrocarbon residue linked, by means of a chemical bond or a divalent organic residue comprising a carbonylamino or a sulphonYlamino group, with a chemical residue comprising an ammonium group; and at least a non fluorinated betaine residue comprising a non-fluorinated aliphatic hydrocarbon residue linked with a betaine residue by means of a divalent organic residue comprising a carbonylamino or sulphonylamino group.
 9. The photographic layer of claim 5, characterized in that the fluorinated surfactant corresponds to the formula: RF - A - Y wherein: RF represents a substantially fluorinated hydrocarbon residue; A is a chemical bond or a divalent organic residue; and Y represents an anionic, non-ionic, or cationic betaine or N-oxide hydrophylic group.
 10. The photographic layer of claim 9, characterized in that RF is a fluorinated alkyl group having from two to eight carbon atoms, A is a chemical bond or a divalent organic residue comprising at least a carbonyl, sulphonylamino, alkylene residue having from one to three carbon atoms, oxygen, carbonylamino, sulphonylamino, aminocarbonyl, aminosulphonyl, ester, polyoxyalkylene having from two to 40 oxyalkylene unities and/or R is an alkyl group having from four to 18 carbon atoms and Z is a betaine hydrophylic group comprising an ammonium group and an anionic group or a group comprising an N-oxide bond.
 11. A photographic element comprising at least a base and a photographic layer according to any of claim
 5. 12. In a photographic element including: a. a base; b. two layers of silver halide emulsion, dispersed in a hydrophylic colloidal binder comprising gelatin, each emulsion layer being coated on separate faces of said base; c. two protective layers, essentially consisting of a hydrophylic colloidal binder comprising gelatin, each protective layer coated on one of said emulsion layers, said protective layer containing at least a non-fluorinated anionic surfactant, the improvement, which lies in that said protective layers contain at least one surfactant having a substantially fluorinated anion or cation and at least a non-fluorinated betaine and/or N-oxide surfactant.
 13. The photographic element of claim 12, characterized in that said fluorinated surfactant is a fluorinated cationic surfactant.
 14. The photographic element of claim 13, characterized in that it contains said fluorinated cationic surfactant comprising a partially or wholly fluorinated aliphatic hydrocarbon residue linked, by means of a chemical bond or a divalent organic residue comprising a carbonylamino or sulphonylamino group, with a chemical residue comprising an ammonium group; and at least a non-fluorinated betaine surfactant comprising a non-fluorinated aliphatic hydrocarbon residue linked with a betaine residue by means of a divalent organic residue comprising a carbonylamino or a sulphonylamino group.
 15. The improved photographic element according to claims 12, characterized in that the fluorinated surfactant corresponds to the formula: RF - A - Y wherein: RF represents a partially or wholly fluorinated hydrocarbon residue; A represents a chemical bond or a divalent organic residue; and Y represents a hydrophylic anionic, non-ionic, cationic, betaine or N-oxide group; and/or the non-fluorinated betaine and/or N-oxide surfactant corresponds to the formula: R - A - Z wherein: R represents a non-fluorinated hydrocarbon residue; A has the same meaning as said above; Z represents a hydrophylic betaine or N-oxide group.
 16. The photographic element of claim 15, characterized in that RF is an alkyl group having from two to eight carbon atoms, A is a chemical bond or a divalent residue at least comprising a carbonyl, sulphonyl, amino, alkylene residue having from one to three carbon atoms, oxygen, carbonylamino, sulphonylamino, aminocarbonyl, ester, polyoxyalkylene having from two to 40 oxyalkylene unities and/or R is an alkyl group having from four to 18 carbon atoms and Z is a hydrophylic betaine group comprising an ammonium and an anionic group or a group comprising an N-oxide bond.
 17. The method of claim 4 wherein the photographic material further comprises at least one protective layer comprising gelatin for said emulsion layer, and where said surfactants are present in at least one of said emulsion and protective layers.
 18. The process of claim 4 wherein the emulsion layer further contains at least one non-fluorinated anionic surfactant.
 19. The process of claim 17 wherein the at least one of said emulsion or protective layers containing the surfactants further contains at least one non-fluorinated anionic surfactant.
 20. The photographic layer of claim 6 wherein said fluorinated surfactant is a fluorinated cationic surfactant.
 21. The photographic layer of claim 6, characterized in that it contains a non-fluorinated anionic surfactant; at least a fluorinated cationic surfactant comprising a partially or wholly fluorinated aliphatic hydrocarbon residue linked, by means of a chemical bond or a divalent organic residue comprising a carbonylamino or a sulphonylamino group, with a chemical residue comprising an ammonium group; and at least a non-fluorinated betaine residue comprising a non-fluorinated aliphatic hydrocarbon residue linked with a betaine residue by means of a divalent organic residue comprising a carbonylamino or a sulphonylamino group.
 22. The photographic layer of claim 6, characterized in that the fluorinated surfactant corresponds to the formula: RF - A - Y wherein: RF represents a substantially fluorinated hydrocarbon residue; A is a chemical bond or a divalent organic residue; and Y represents an anionic, non-ionic, or cationic betaine or N-oxide hydrophylic group.
 23. The photographic layer of claim 9 wherein at least one of the non-fluorinated betaine and N-oxide surfactants correspond to the formula: R - A - Z wherein: R is a non-fluorinated hydrocarbon residue, A is a chemical bond or a divalent organic residue, and Z represents a betaine or N-oxide hydrophilic group.
 24. The photographic layer of claim 6 wherein at least one of the non-fluorinated betaine and N-oxide surfactants correspond to the formula: R - A - Z wherein: R is a non-fluorinated hydrocarbon residue, A is a chemical bond or a divalent organic residue, and Z represents a betaine or N-oxide hydrophilic group.
 25. The photographic layer of claim 22, characterized in that RF is a fluorinated alkyl group having from two to eight carbon atoms, A is a chemical bond or a divalent organic residue comprising at least a carbonyl, sulphonylamino, alkylene residue having from one to three carbon atoms, oxygen, carbonylamino, sulphonylamino, aminocarbonyl, aminosulphonyl, ester, polyoxyalkylene having from two to 40 oxyalkylene unities and/or R is an alkyl group having from four to 18 carbon atoms and Z is a betaine hydrophylic group comprising an ammonium group and/or an anionic group or a group comprising an N-oxide bond.
 26. A photographic element comprising at least a base and a photographic layer according to claim
 6. 27. The improved photographic element according to claim 14 characterized in that the fluorinated surfactant corresponds to the formula: wherein: RF represents a partially or wholly fluorinated hydrocarbon residue; A represents a chemical bond or a divalent organic residue; and Y represents a hydrophylic anionic, non-ionic, or cationic betaine or N-oxide group; and/or the non-fluorinated betaine and/or N-oxide surfactant corresponds to the formula: R - A - Z wherein: R represents a non-fluorinated hydrocarbon residue; A has the same meaning as said above; Z represents a hyDrophylic betaine or N-oxide group.
 28. The photographic element of claim 27, characterized in that RF is an alkyl group having from two to eight carbon atoms, A is a chemical bond or a divalent residue at least comprising a carbonyl, sulphonyl, amino, alkylene residue having from one to three carbon atoms, oxygen, carbonylamino, sulphonylamino, aminocarbonyl, ester, polyoxyalkylene having from two to 40 oxyalkylene unities and/or R is an alkyl group having from four to 18 carbon atoms and Z is a hydrophylic betaine group comprising an ammonium and an anionic group or a group comprising an N-oxide bond. 